Glycine vs Melatonin for sleep
Short answer: For sleep, more users report improvement with Glycine — 87% of 255 reports, versus 78% of 915 for Melatonin.
Glycine has 392 meta-analyses and 620 randomized trials on PubMed; Melatonin has 688 and 1,128.
Based on 695 reports about Glycine and 1,370 about Melatonin. Not medical advice.
| Glycine Supplement | Melatonin Supplement | |
|---|---|---|
| Users say it helped | 70%helped299 reports · high confidence | 42%helped726 reports · high confidence |
| Verdict | Mostly positive | Mixed |
| Research | AResearch: Strong | AResearch: Strong |
| Meta-analyses / RCTs | 392 / 620 | 688 / 1,128 |
| Mainly used for | ||
| Sleep % reporting improvement | 87% (255) | 78% (915) |
| Anxiety % reporting improvement | 78% (60) | 44% (16) |
| Mood % reporting improvement | 87% (39) | 32% (37) |
| Energy % reporting improvement | 94% (17) | 32% (25) |
| Focus % reporting improvement | 62% (13) | 38% (8) |
| Common side effects | vivid dreams, drowsiness, fatigue, brain fog | drowsiness, vivid dreams, fatigue, depression |
| Typical dose reported | 2 g / daily | 0.5 mg / bedtime |
In studies using high-throughput metabolomics, several blood amino acids appear to be consistently associated with the risk of developing type 2 diabetes.
Diabetes Care, 2016 ↗“2 grams with 200mg magnesium before bed gives me crazy good sleep. Crazy vivid dreams.”
Overall, eszopiclone and lemborexant had a favorable profile, but eszopiclone might cause substantial adverse events and safety data on lemborexant were inconclusive. Doxepin, seltorexant, and zaleplon were well tolerated, but data on efficacy and other important outcomes were scarce and do not allow firm conclusions. Many licensed drugs (including benzodiazepines, daridorexant, suvorexant, and trazodone) can be effective in the acute treatment of insomnia but are associated with poor tolerability, or information about long-term effects is not available. Melatonin, ramelteon, and non-licensed
Lancet, 2022 ↗“I have taken it nightly for 19 years. Doses ranging from .1 to 10mg. Right now I take 3mg per night. It helps me sleep.”
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Percentages come from first-hand user reports and are not clinical outcomes. Talk to a doctor before starting, stopping or combining anything. How we rate